1. Field of the Invention
The present invention relates to a coating and developing system for coating a substrate, such as a semiconductor wafer or an LCD substrate, namely, a glass substrate for a liquid crystal display, with a resist solution by a coating process and processing the substrate by a developing process after exposure, a coating and developing method to be carried out by the coating and developing system, and a storage medium.
2. Description of the Related Art
A manufacturing process for manufacturing a semiconductor device or an LCD substrate forms a resist patter on a substrate by photolithography. Photolithography includes a series of steps of coating a surface of a substrate, such as a semiconductor wafer (hereinafter, referred to as “wafer”) with a resist film by applying a resist solution to the surface, exposing the resist film to light through a photomask, and processing the exposed resist film by a developing process to form a desired pattern.
Generally, those processes are carried out by a resist pattern forming system constructed by connecting an exposure system to a coating and developing system for coating a surface of a substrate with a resist solution and developing an exposed film. Such a resist pattern forming system is proposed in, for example, JP-A 2006-203075. In such a coating and developing system, an area in which modules for processing a substrate before the substrate is subjected to an exposure process, and an area in which modules for processing the substrate processed by the exposure system are vertically arranged in layers to further increase the processing rate of the coating and developing system, carrying devices are installed respectively in those areas to improve carrying efficiency by reducing load on the carrying devices so that the throughput of the coating and developing system may be increased.
Referring to FIG. 17, showing this known resist pattern forming system, a carrier block S1, a processing block S2 and an interface block arranged in that order are connected. The processing block S2 is built by stacking up developing blocks B1 and B2 for carrying out a developing process, a coating block B4 for carrying out a resist solution application process, and antireflection film forming blocks B3 and B5 for carrying out an antireflection film forming process before and after the resist solution application process. The blocks B1 to B5 of the processing block S2 are provided with wet-processing units for carrying out wet processes, such as the developing process, the resist solution application process and the chemical solution application process for applying a chemical solution for forming an antireflection film, shelf units formed by stacking up processing units for carrying out processes before and after the wet processes, carrying devices A1 to A5 for carrying wafers W to and from the modules of the wet-processing units and the shelf units, and exclusive transfer arms for transferring wafers W through the shelf units U5 and U6 to and from the blocks B1 to B5.
A transfer arm C installed in the carrier block S1 carries a wafer W to the processing block S2, and the carrying devices A1 to A5 and transfer arms D1 and D2 carry the wafer W to the desired processing units. Thus loads on the transfer arm C, the carrying devices A1 to A5, and the transfer arms are reduced to improve the throughput of the resist pattern forming system.
The resist pattern forming system is provided, for example, with three set-processing units, and the processing units. The number of the processing units corresponds to that of the wet-processing units. Although this resist film forming system can process wafers at a throughput on the order of, for example, 180 wafers/hr, the market demands for a system capable of processing wafers at a high throughput in the range of 200 to 250 wafers/hr.
If the numbers of wet-processing modules of the developing block B1 and the coating block B3, and the processing units for carrying out processes before and after the wet processes are increased with an aim to improve the throughput, loads on the carrying devices increase, which makes the improvement of the throughput of the system difficult. The number of the stacked developing blocks B1 may be increased and the number of the wet-processing modules and the processing units may be increased for the same purpose. However, loads on the transfer arms for transferring wafers to and from the blocks B1 to B5 increase inevitably, which also makes the improvement of the throughput of the system difficult.
The throughput may be improved by using a plurality of processing blocks like the processing block S2. If the plurality of processing blocks S2 are installed to increase the number of the coating blocks B4 or the like, wafers are carried to the coating block B3 of the processing block S2 near the carrier block S1 and to the coating block B3 of the processing block S2 remote from the carrier block S1 along different carrying passages, respectively. Therefore the carrying passages are complicated and the creation of a carrying program requires a very complicated procedure.